Fortnite's revenue is growing at its slowest pace ever but it is still beating out cable's top shows

Fortnite is one of the biggest games in the world with 125 million players, and already, the free-to-play game topped $1 billion in revenue in May, according to gaming research firm SuperData. But the money-making giant has seen a drastic slowdown in its revenue growth to 2 percent from May to June.

Despite the deceleration, the game's loyal fan base is stronger than ever.

There are 3.2 million broadcasters on streaming site Twitch. Since Epic Games launched the battle royale version of "Fortnite," the game has taken over the site. In September 2017, "Fortnite" made up less than 1 percent of the content produced by streaming channels. Fast forward to August 2018, and that number has jumped to 49 percent.

In June, a Fortnite event called Friday Fortnite pulled in 8.8 million unique viewers. To put that in perspective, the season finale of AMC's "The Walking Dead" brought in 7.9 million viewers, the first round of the NFL draft raked in 5.3 million and the season premier of "Westworld" reeled in 2.1 million.

When the first "Fortnite" World Cup launches in 2019, you can expect huge viewership numbers from audiences watching their favorite streamers. According to Statista, the number of gaming viewers worldwide will reach an estimated 743 million people in 2019.